A number of conditions other than pregnancy, including trophoblastic disease and certain nontrophoblastic neoplasms, cause elevated levels of hCG. These diagnoses should be considered if appropriate to the clinical evidence.

If a urine specimen is too diluted (low specific gravity), it may not contain representative levels of hCG. If pregnancy is suspected, ask the patient to collect first morning urine 48 to 72 hours later and repeat the test.

Because of the high sensitivity of the assay, specimens tested as positive during the initial days after conception may later be negative due to natural termination of the pregnancy.

A definitive clinical diagnosis should not be based on the results of a single test but should be made by the physician after evaluation. Blood specimens may be sent to the Clinical Laboratories for confirmatory testing.